Genitourinary Medicine Flashcards
What is the aetiology of bacterial vaginosis?
It is caused by an overgrowth of predominantly anaerobic organisms in the vagina. They replace lactobacilli, the dominant bacteria present in the normal vagina. pH increases from 4.5 to as high as 6.
IT IS NOT AN STI
What are the risk factors for bacterial vaginosis?
Sexual activity New sexual partner Other STIs Ethnicity (more common in Afro-Caribbean women) Copper IUD Vaginal douching Smoking
What is the presentation in bacterial vaginosis?
Offensive, fishy-smelling vaginal discharge without soreness or irritation
White/grey discharge
On examination: a thin layer of white discharge covering the vaginal wall
What is the differential diagnosis for bacterial vaginosis?
Other vaginal infections
Other benign causes of vaginal discharge
Tumours of the vulva, vagina, cervix or endometrium
Postmenopausal discharge due to atrophic vaginitis
Vaginal discharge after gynaecological surgery
What investigations would you perform for bacterial vaginosis?
pH >4.5
Triple swabs for MC&S - Clue cells on Gram-stained slides
A fishy odour produced when 10% KOH is added to the discharge
What are the risks associated with bacterial vaginosis?
Increased risk of preterm labour
Intra-amniotic infection
Increased susceptibility to HIV
Post-termination sepsis
How is bacterial vaginosis treated?
PO metronidazole 2g one off or 400-500mg BD for 7 days
Clindamycin 2% gel applied to the vagina OD for 7 days
What is the pathogenesis involved in candidiasis?
95% of cases are due to candida albicans
5% of cases are due to candida glabrata
What are the risk factors for candidiasis?
Pregnancy Steroids Antibiotic use Immunodeficiency DM Chemotherapy Vaginal foreign body COCP
What are the symptoms of candidiasis?
Pruritus vulvae Vulval soreness White "cheesy" discharge - non-offensive Dyspareunia (superficial) Dysuria (external)
What are the signs of candidiasis?
Vulval erythema
Vulval oedema
Satellite lesions
Excoriation
What is the differential diagnosis for candidiasis?
BV Trichomonas STIs Atrophic vaginitis Lichen sclerosus Contact dermatitis Eczema Psoriasis Mechanical irritation Retrovesical fistula UTI Helminthic infection
What investigations would you perform for candidiasis?
Routine vaginal swabs are not required
If swabs are taken for MC&S - hyphae and spores
MSU to rule out UTI
What is the management for candidiasis?
Topical clotrimazole - cream or pessary
Oral fluconazole - 150mg single dose
If C. galbrata, try topical nystatin or oral imidazole for 7-14 days
What pathogen causes gonorrhoea?
Neisseria gonorrhoea, a Gram-negative intracellular diplococcus only infecting humans. It typically infects the GU tract, rectum, pharynx and conjunciva.
What are the risk factors for gonorrhoea?
Young age Previous STI Co-existant sTIs New/multiple sexual partners Recent sexual activity abroad Certain sexual activities e.g. anal intercourse Inconsistent condom use History of drug use or commercial sex work
What are the symptoms of gonorrhoea?
Discharge Dysuria Anal discharge Intermenstrual bleeding Pelvic pain
What are the signs of gonorrhoea?
Men: mucopurulent or purulent urethral discharge, epididymal tenderness/swelling or balanitis
Women: mucopurulent endocervical discharge, easily induced contact bleeding of the endocervix, pelvic tenderness, normal examination
Children: acute conjunctivitis (+ purulent discharge), usually bilateral and occuring <48 hours after birth
What investigations would you perform for gonorrhoea?
Swab for MC&S
Urine sample for NAATs
Blood culture and joint aspiration if disseminated GC is suspected
What is the management of gonorrhoea?
Ceftriaxone 500mg IM stat and azithromycin 1g orally stat
A test of cure is recommended in all cases
What are the different types of herpes simplex virus?
Type 1 - usually causes oral lesions but can also cause genital lesions if transferred
Type 11 - sexually transmitted, can cause genital lesions
What are the risk factors for HSV infection?
Multiple sexual partners Previous history of STIs Early age of first sexual intercourse Unprotected sexual encounters MSM Female gender HIV infection
What are the symptoms of HSV infection?
Febrile, flu-like prodrome
Tingling neuropathic pain in the genital area/buttocks/legs
Extensive painful blisters/ulcers in the genital area
Tender lymph nodes
Local oedema
Dysuria
Vaginal/urethral discharge
What investigations would you perform for HSV infection?
Viral culture
Swab from the base of an ulcer for PCR
Serology (can take up to 12 weeks to become positive after the primary infection)
What is the differential diagnosis for HSV infection?
Vulvo-vaginal candidiasis
Other STIs
Skin conditions e.g. scabies, psoriasis or contact dermatitis
What is the management for HSV infection?
Referral to the GUM clinic
Aciclovir 400mg TDS or valaciclovir 500mg BD for 5 days
Supportive management e.g. saline bathing, oral painkillers, topical lidocaine 5%
What is the pathology of HPV infection?
There are >100 types of HPV.
HPV types 6 and 11 account for >90% of cases
Types 16 and 18 are associated with a high risk of neoplastic transformation
What are the symptoms of a HPV infection?
Presence of lesions, usually painless but may cause itching, bleeding or dyspareunia
A relevant sexual history should be obtained to assess the risk of other STIs and sexual health needs
What are the signs of HPV infection?
Warts on moist non-hairy skin are usually soft and non-keratinised whereas those on dry, hairy skin are more likely to be firm and keratinised.
Warts may be broad-based or pedunculated, pigmented or not. Warts are often found on areas subject to trauma on sexual intercourse.
What investigations would you perform for HPV infection?
Diagnosis by biopsy and viral typing is not routinely required. An appropriate screen for other STIs should be carried out.
What is the management for HPV infection?
Referral to a sexual health clinic
1/3 of warts regress spontaneously within 6 months
Topical creams
Cryocauterisation, diathermy, surgical removal or laser therapy
What is the immunology of HIV?
HIV binds to CD4 receptors on helper T lymphocytes, monocytes, macrophages and neural cells. CD4+ cells migrate to lymphoid tissue and the virus replicates to produce new virions. These are released and infect new CD4 cells. As infection progresses, depletion or impaired function of CD4+ cells leads to reduced immunity.
What are the 5 stages of HIV infection?
Acute infection
Seroconversion
Persistent generalised lymphadenopathy (only 30% of patients)
AIDS-related complex (increased temp, night sweats, diarrhoea, weight loss +/- minor opportunistic infections)
AIDS
How is HIV diagnosed?
Serum HIV-Ab by ELISA
HIV RNA PCR
Core p24 antigen in plasma
What is the treatment for HIV?
HAART - highly active anti-retroviral therapy
1 NNRTI + 2 NRTIs -or- PI + 2 NRTIs
NNRTI - non-nucleoside reverse transcriptase inhibitor e.g. nevirapine, efavirenz
NRTI - nucleoside reverse transcriptase inhibitor e.g. tenofovir, abacavir, zidovudine, didanosine
PI - protease inhibitor e.g. indinavir, ritonavir, saquinavir
How is HIV monitored?
CD4+ T cell count (per microlitre)
HIV viral load (RNA copies/ml)
What are some AIDS-defining infections?
Candidiasis: oesophageal/lung Extrapulmonary cryptococcus Cryptosporidiosis for >1 month CMV: any organ except liver, spleen and lymph nodes Mycobacterium TB Toxoplasmosis of internal organs HSV with mucocutaneous ulcer >1 month Pneumocystis jiroveci pneumonia (PCP) Recurrent bacterial pneumonia
What are some AIDS-defining neoplasms?
Invasive cervical carcinoma
Kaposi’s sarcoma
Primary CNS lymphoma
Non-Hodgkin’s lymphoma
What are 2 AIDS-defining conditions that are a direct HIV effect?
HIV dementia/encephalopathy
HIV-associated wasting
What are the risk factors for chlamydia?
Age <25y Sexual partner positive for chlamydia >/= 2 sexual partners Recent change in sexual partner Lack of consistent use of condoms Non-barrier contraception Infection with another STI Poor socio-economic status
What are the symptoms of chlamydia?
Female: vaginal discharge, dysuria, vague lower abdominal pain, fever, IMB or PCB, deep dyspareunia
Male: unilateral testicular pain +/- swelling
What are the signs of chlamydia?
Female: friable inflamed cervix, mucopurulent endocervical discharge, abdominal tenderness, pelvic adnexal tenderness, cervical excitation
Male: epididymal tenderness, mucoid or mucopurulent discharge
Perineal fullness due to prostatitis
What investigations would you perform for chlamydia?
NAATs
Vulvovaginal swab in females
First catch urine sample in males
What is the management for chlamydia?
Antibiotics:
Doxycycline 100mg BD for 7 days - contraindicated in pregnancy
Single dose of 1g of azithromycin - can use in pregnancy and breastfeeding
What is the aetiology of trichomonas?
It is a flagellated protozoan. In adults, transmission is almost exclusively through sexual intercourse.
What are the symptoms of trichomonas?
Female: vaginal discharge - frothy, yellow, vulval itching, dysuria or offensive odour, lower abdominal pain
Men: usually asymptomatic, dysuria, presence of urethral discharge
What are the signs of trichomonas?
Female: Local inflammation with vulvitis, vaginitis and cervicitis - strawberry cervix
Male: no abnormal signs
What is the differential diagnosis for trichomonas?
Other vaginal infections e.g BV, candidiasis, chlamydia
Other benign causes of vaginal discharge e.g. physiological, pregnancy
Atrophic vaginitis
Other causes of prostatitis, cystitis
What investigations would you perform for trichomonas?
NAATs
High vaginal swab from the posterior fornix
Self-administered vaginal swab
Urethral culture or culture of first void urine for men
What is the management for trichomonas?
Oral metronidazole 2g as a single dose
Oral metronidazole 400-500mg BD for 5-7 days
Treat partner, regardless of results
